In recent years, digital cameras (image sensing devices) which can sense an image and can convert the sensed image into digital image data by a simple operation have been popularly used. When an image sensed by such camera is printed and is used as a photograph, it is a common practice to temporarily download the sensed digital image data from a digital camera to a PC (computer), to execute an image process by that PC, and to output the processed image data from the PC to a color printer, thus printing an image.
By contrast, a color print system which allows a digital camera to directly transfer digital image data to a color printer without the intervention of any PC and can print it out (to be referred to as a direct print process hereinafter), a so-called photo-direct (PD) printer which can mount a memory card, which is mounted on a digital camera and stores sensed images, and can read and print sensed images stored in the memory card, and the like have recently been developed.
Such direct print process is originally a model-dependent print function that can be implemented between a camera and printer of an identical manufacturer. However, in recent years, the standardization in these industries has been made, and an environment that allows a direct print process by connecting a camera and printer of different manufacturers irrespective of manufacturers has been created.
Such printer device may receive and print image data from various devices such as a portable phone, PDA, and the like in addition to the aforementioned digital camera. Also, the printer itself has various functions, and exchanges function information with such devices.
However, such function information often includes those which cannot be exchanged between these devices. For example, when a partner device does not consider a given function at all, it cannot interpret such function information even if such information is transmitted. In such case, the device that has transmitted the function information cannot determine whether the partner device does not support the function, or no response returns due to a communication error or the like. For this reason, when such problem has occurred, each device may transfer image data and issue a print instruction while it cannot be determined whether or not the partner device supports the function.
In this case, for example, the contents of a UI displayed on a camera which requests printing by sending image data become different from the functions of a printer as the partner device in practice, and the user of the camera who wishes the printing cannot obtain a print result he or she intended, resulting in confusion. In such case, the camera may give a print instruction to the printer, by using a print function in which the printer does not have, and as the result, a print result that the user did not intend is obtained.